(1) Field of the Invention
The present invention relates to an air wiper which is arranged in a vicinity of a viewing surface through which a driver views an object, and can remove substances such as drops of water, blur or the like, adhering to the viewing surface. The viewing surface is, for example, a side mirror such as a fender mirror or a door mirror and the front side window of an automobile. Particularly the present invention relates to an air wiper which can remove adhered substances from the viewing surface efficiently and occupies a small volume.
(2) Description of Related Art
When a man drives a vehicle, such as an automobile or a truck on a highway, he confirms rearward vehicle safety using a side mirror such as a door mirror or a fender mirror. However, in inclement weather, such as rain or dense fog, drops of water adhere or blur is produced on the glass mirror surface and safety confirmation may become difficult. Also in order to see the side mirror through the front side window, the side mirror surface cannot be seen clearly even when the drops of water, the blur or the like adhere to the surface of the front side window glass. As a result, safety confirmation using the side mirror becomes difficult.
Therefore, various air wipers have been proposed where heated air or the like is forcibly discharged onto the viewing surface of the side mirror and the front side window glass, and substances adhering to the viewing surface of the side mirror and the front side window glass are removed.
For example, JP-U 61-68956 discloses that pressurized heated air is discharged from a number of jet holes provided at a side part of the door mirror.
In the prior art air wiper, however, since the heated air must be discharged simultaneously over the entire surface of the mirror, a plurality of the jet holes are provided or a large diameter jet hole is provided. Therefore, since the area of the opening of jet hole becomes larger, the speed of the jetted air becomes slower. As a result, in order to remove the adhering substances easily, the velocity of the air must be raised by a fan, a compressor or the like. Also, since the air must be forcibly discharged over a wide region such as the entire surface of the mirror, the jet holes must be arranged over the wide region and the space occupied by the air wiper is apt to become large.
In view of the above-mentioned aspects, an object of the present invention is to provide an air wiper which can remove adhered substances such as drops of water, blur or the like, adhering to a viewing surface when a driver views a visual object through, for example, a side mirror, a front side window or the like. It is another object of the present invention to provide an air wiper which can remove these substances efficiently, and occupy a small space.